package netudp;

import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.DatagramPacket;
import io.netty.channel.socket.nio.NioDatagramChannel;
import io.netty.util.CharsetUtil;

public final class TheMomentClient {

    static final int PORT = Integer.parseInt(System.getProperty("port", "7686"));

    public static void main(String[] args) throws Exception {

        EventLoopGroup group = new NioEventLoopGroup();

        try {
            Bootstrap b = new Bootstrap();
            b.group(group);
            b.channel(NioDatagramChannel.class);

            // the udp packet is sending to this address and port
            b.remoteAddress("127.0.0.1",PORT);

            b.handler(new TheMomentClientHandler());

            // bind(0) means the port is divided by system at random
            Channel ch = b.bind(0).sync().channel();

            // Broadcast the QOTM request to port 8080.
            ch.writeAndFlush(new DatagramPacket(
                Unpooled.copiedBuffer("[BEAT]", CharsetUtil.UTF_8),
                SocketUtils.socketAddress("127.0.0.1", PORT))).sync();

            // TheMomentClientHandler will close the DatagramChannel when a
            // response is received.  If the channel is not closed within 5 seconds,
            // print an error message and quit.
            if (!ch.closeFuture().await(5000)) {
                System.err.println("[LOG]: Request from the server is timed out.");
            }
        } finally {

            group.shutdownGracefully();
        }
    }
}